German Auslegeschrift 1 139 758 ('758) discloses an electromechanical shift device for change-speed gearboxes of motor vehicles wherein a gearshift member cooperating with the gear shifting element of the change-speed gearbox is movable in two shifting movements substantially transverse to one another. A rotary movement is produced by a solenoid and a linear movement is produced by an electric motor. The motor controllably moves an actuating shaft carrying an axially movable selector sleeve. The '758 shift device has the disadvantage that the radial movement, which determines the shift gates, starting from a neutral position, can only serve two further shift gates, so that at most a shift device with three shift gates can be obtained.
German specification 33 31 223 ('223) also discloses an electromechanical shift device for change-speed gearboxes of motor vehicles. The '223 specification discloses an electromechanical shift device in the form of a complicated gear mechanism comprising a worm gear unit and a rack and pinion gear unit. In the device of the '223 specification, a linear preselection movement can be applied to a gearshift member, the engagement movement is then effected by manual actuation of the manual gear lever of the change-speed gearbox. The electromechanical shift device of the '223 specification is only semiautomatic and is quite expensive to build because of this gear mechanism.
It would be desirable to provide an inexpensive electromechanical shift device of the kind referred to having the usual three gates, and which, at little additional cost, can also serve for more than three gates.